In the field of mobile communications, subscribers now expect ever smaller and lighter radio telephones which they can carry with them at all times and which, in addition, are easy to operate.
At present mobile radio telephones usually have a numeric keypad for inputting directory numbers but also for inputting characters in order to store, for example, the name of a subscriber with the associated directory number. Later, the name of the subscriber is retrieved from the memory of the telephone and the associated directory number is automatically dialled.
Furthermore, it is possible in today""s radio telephone networks to send short messages via the so-called Short Message Service (SMS). These short messages are input via the numeric keypad which, for this purpose, is set to a mode which makes it possible to input letters.
In addition to the usual numeric keypad, mobile radio telephones also have some additional function keys and a menu structure, for example to facilitate the selection of the name of a stored subscriber. In the final analysis, however, utilization of the functions described above with the usual keypads remains extremely difficult and cumbersome.
As the miniaturization of mobile radio telephones increases, however, the usual keypad will also no longer be suitable for carrying out the functions described above. This is known, for example, from pocket calculators integrated in wrist-watches which can now only be operated with the point of a pen or similar objects.
To facilitate at least the selection of directory numbers from a memory, today""s mobile radio telephones are equipped with a small hand wheel or with multi-function keys which, however, do not provide any help when inputting words.
A mobile phone which is constructed in the form of a pen and which has a digit input unit in which the digits are preselected by rotating the pen point and selected by pressing a button is already known from DE 42 94 697 C2. The mechanical structure of this mobile telephone is quite complicated and therefore susceptible to faults. In addition, a large amount of time is needed for inputting information.
Last but not least, a dictating pen for deaf/mute persons is known from JP 7-271 293. The dictating pen contains in its point an acceleration sensor device which detects the movement of the pen and converts characters written with it into language. The electrical voice signals can also be coupled into a telephone line, either directly or via a microphone connection of a microphone present in a telephone handset.
The invention is based on the object of simplifying the inputting of information and making it more flexible with respect to the type of information which can be input even in mobile radio telephones which are miniaturized further.
In the method according to the invention, information is input into a mobile radio telephone via its input data channel by appropriately moving a motion detector which belongs to the radio telephone and senses this movement.
Mobile radio telephones usually have an acoustic channel via which information spoken using a microphone can be input into the telephone. In addition, there is an input data channel via which information can be input into the telephone, for example by keys or other mechanical input means. The invention makes use of this input data channel for additionally transmitting signals from the motion detector via it, which makes it possible to increase the range of data to be input with respect to their type and, by using the motion detector, to save a large number of input keys so that it is possible not only to simplify the inputting of information via the input data channel but also, by saving input means, to enable the mobile radio telephone to be miniaturized further.
Any information which can be represented graphically by moving the motion detector can be input via the input data channel. This can be letters, digits, symbols, lines or other graphic elements or figures or technical representations composed of these.
The information input in this manner can be used for a wide range of purposes. For example, it can be input for carrying out dialling processes, for the transmission of short messages or longer texts to a subscriber or even for transmitting entire technical representations or tables, the information transmitted to the subscriber then being displayed there, for example on a suitably constructed monitor or can be output via a printer, for example. In this case, the monitor could be present, for example, in a mobile communication device which is equipped with telephone functions whilst the printer, for example, could be that of a facsimile machine equipped with telephone functions.
According to one embodiment of the invention, the entire radio telephone, and with it the motion detector, is moved for inputting the information. In contrast, according to another embodiment of the invention an input device belonging to the radio telephone and accommodating at least the motion detector can be moved for inputting the information. Both options allow the information to be input in a particularly simple manner and thus lead to very good manageability of the telephone.
The information input in this manner can in principle be transmitted as it is from the telephone to the subscriber. However, it is also possible to compare the input information with information already present in the radio telephone for recognition of the input information. This variant is selected especially if a dialling process is to be carried out via the input information or if it is intended for transmitting short messages in text form or longer texts. In this case, greater reliability with respect to the correctness of the information input or transmitted is achieved.
The information input or recognized can also be temporarily stored in the radio telephone in a further development of the invention. With respect to the input information, this applies, for example, to graphic representations which are first generated by the input process and are stored in a buffer memory before the stored data are sent to the receiver, for example in packet form. With respect to detected information, this applies, for instance, to input telephone numbers which are first temporarily stored before a dialling process can be initialized.
On the other hand, information input or recognized can naturally also be transmitted on-line, although in some cases this may require more transmitting time, especially where drawings are transmitted.
If information is input via the input device which is separate from the rest of the radio telephone, the information can be transmitted from the said device to the rest of the radio telephone via a cable or via a radio link in order to be transmitted from there to the subscriber, possibly after further processing. During this process, the information input or recognized can be displayed by the radio telephone itself or in the case of the two-part construction, by the input device or the rest of the radio telephone. A user can therefore check the input information with respect to its correctness.
To ensure reliable operation of the radio telephone, it can be switched to an information input mode which is selected from a menu by operating a selection device for inputting information. In this connection, predetermined characters input in the information input mode can be used for grouping input information. Thus, input digits can be assembled into complete telephone numbers, characters into character groups, letters into words and drawing elements into a graphic representation or technical drawings.
According to an advantageous embodiment of the invention, accelerations in different directions are measured by the motion detector for inputting information. This detector can exhibit sufficient acceleration sensors to sense movements in one plane or movements in space. Advantageously, therefore, two or three acceleration sensors, respectively, which measure accelerations in mutually perpendicular directions are used in the motion detector. The input information can be deduced from the measured accelerations, appropriate algorithms being available for this purpose. If it is intended, for example, to input characters (letters or digit), these algorithms, which are generally known, ensure unambiguous recognition of the characters irrespective of which hand a user is using for guiding the telephone or the input device or how the telephone or input device are held in space. If necessary, the radio telephone can be informed in a preparatory step where left and right are located, as an orientation aid, namely by drawing an appropriate line and temporarily storing the corresponding acceleration vector. Recessed cups for the fingers can also be of assistance for orientating the writing position of the telephone.
Naturally, a radio telephone of the type according to the invention must also know the point from which movements are to be interpreted as information to be input so that it does not continuously record every movement. For this purpose, appropriate initialization means can be present, especially in the motion detector equipped with acceleration sensors, for example a switch at the point of the radio telephone or the input device which is operated by placing it on a base and thus signals that information input thereafter is to be regarded as useful information. This switch could also be activated by a voice command.
In a further embodiment of the invention, the motion detector can also measure distances travelled by it in different directions on a base for inputting information. This distance measurement can be carried out by means of a roller ball such as is used, for example, in computer mice. It is also possible, however, to perform the distance measurement by optically scanning lines present on the base by means of a transmitter and a number of receivers. If lines extending in different directions exhibit information about these directions, for example different colours, a position can be determined and thus a distance measured by counting the respective lines in the different directions. The measured distances can in this case, as in the case of detection by means of a roller ball, then be processed by suitable algorithms in order to reproduce the input information electronically. In this connection, character recognition programs can also be used in order to be able to recognize unambiguously, for example, input digits or letters.
According to the invention, a mobile radio telephone contains a motion detector for inputting information represented by movement of the motion detector via the input data channel of the telephone. As already mentioned, the telephone can be constructed in one part in order to obtain a compact unit. However, it can also comprise an input device which is separate from a main telephone unit and in which the motion detector is accommodated. In this arrangement, radio telephone or input device can be constructed in the form of a pen, leading to an extraordinarily miniaturized model of a radio telephone. If the input device is also equipped with loudspeaker and microphone, it can be used as a voice communication unit and can communicate with the main telephone unit via a cable or cordless link like infrared, radio or ultrasonic link.
As already mentioned, the mobile telephone according to the invention can contain a character recognition device for recognizing information by comparing the input information with information already present. The recognition device is for example able to recognize characters (letters and numbers) and symbols. Also signs patterns and signatures stored by the user can be recognized. The character recognition device may be activated in a particular operation mode to be set in the radio telephone. In this arrangement, the recognition device can be either in the input device or in the main telephone unit in the case of the two-part radio telephone. In the last-mentioned case, this allows the input device to be of simpler and even lighter construction. The recognition unit can also be partitioned between the input device and the main telephone unit. The amount of data to be transmitted between the input unit and the main telephone is reduced if a kind of preprocessing of the recognition is carried out within the input device.